Teleprinter



y G. EHRENBERG I 2,375,902

TELEPRINTER Filed Jan. 25, 1941 \NVENTOR 61/3734 [AWE/V8586 ATTORN EY.

Patented May 15, 1945 TELEPRINTER Gustav Ehrenberg, Berlin-Adlershof, Germany; vested in the Alien Property Custodian Application January 25, 1941, Serial No. 375,971 In Germany July 26, 1939 2 Claims.

This invention relates to improvements in teleprinters.

In the teleprinting art it is usual to combine a transmitter with a receiver to form a unit so as to enable two-way Working to be carried out. In certain cases this arrangement presents, however, disadvantages.

This is, for instance, the case in railway traffic signalling systems. In general, two lines end at train signalling stations. It is true that a simultaneous two-way working of these two lines may in general be dispensed with; however, each of the two lines must be ready for "receiving signals.

According to the invention a particularly advantageous apparatus is employed for such operating conditions. The inventionconsists in combining a transmitter and various receivers to form a unit in such a manner that the transmitter and one of the receivers may alternately cooperate with a remote apparatus so as to effect two-way working, while the other receivers receive the text to be transmitted from the other remote transmitters.

In such an apparatus all receivers, preferably two receivers being employed, are always connected to the corresponding lines. Consequently, in urgent cases which occur particularly when the train travels at a high speed, signals can always be received over both lines. As compared to the use of two complete telegraph transmitters and receivers the apparatus according to the invention is much simpler, as only one transmitter with a keyboard and a drivin motor is necessary. The number of the receivers may 'be adapted to the prevailing operating conditions. Known connections for the remote control may be employed for starting the apparatus.

If only one line is employed at a certain station the connection may be carried out in such a manner that the second receiver serves as a standby. In this case a corresponding doublethrow switch is furthermore provided.

The apparatus with various receivers may, however, :be used preferably at stationswhich are connected to one or more lines passing by the stations, for instance, intermediate stations connected to district lines, block stations connected to train signalling lines, etc. It may also be employed if lines passing by and ending at the stations are to be connected.

The receivers, the transmitter and the motor are preferably arranged on a common base plate so as to attain a self-contained apparatus. The transmitter and receivers, each of which is provided with a separate driving coupling, are driven by the common motor through a gearing.

In the accompanying drawing, is shown an embodiment of the invention in diagrammatic form.

Fig. 1 shows a side elevational view of the apparatus and Fig. 2 the top view thereof.

On the base plate I is secured a motor 2 which drives through a pinion 3 a gear 4 mounted on the shaft 5. On the shaft 5 is also mounted a gear 6 which in turn drives the gears l and 8..

The gear 4 drives a further gear 9 secured to the shaft l 0 on the end of which there is mounted the coupling II. On the transmitting shaft I2 is arranged the second disk of the friction coupling II. The coupling is released in a known manner through the bars l3 and M by depressing one of the keys l5 for one rotation.

The gear 1 drives the receiver shaft I! of the one receiver through the coupling [6. The coupling is stopped by the armature of the receiving magnet I8 in a known manner (not shown) until the arrival of the startin impulse and is then released for one rotation. The printing of the letters on the paper tape I9 is effected in the usual manner, for instance, by building up or forming the image of the letters or character elements, as is described in the U. S. Patent No. 2,139,352. The receiver may, however, be also operated on any other known telegraphic principle; for instance, on the five-unit code or the facsimile principle. The typewheel is inked by the ink roller 2|, while the paper tape I9 is pressed against the typewheel 20 by the spring 22 of the printing hammer 23. In exactly the same manner the gear 8 drives through the coupling 24 the shaft 25 of the second receiver which is controlled by the armature of the receiving magnet 26. The parts of the second receiver correspond exactly to the parts of the first receiver so that a further description thereof is not deemed necessary.

If a keyl5 of the apparatus shown in Figs. 1 and 2 is depressed, the coupling H is released for one rotation and the transmitter transmits the corresponding series of impulses. The receiver lying in the same line prints the text transmitted and at the same time the text transmitted from a separate remote apparatus may be received on the second receiver.

What is claimed is:

1. Transmitting and receiving apparatus for a printing telegraph system, comprising a base, two receivers mounted on said base a transmitter also mounted on said base, three shafts individual to said common shaft, means for locking said individual shafts against rotation, key controlled means for unlocking the transmitter shaft, and individual receiver magnets for unlocking the re- 4 ceiver shafts.

2. Transmitting and receiving apparatus for a printing telegraph system, comprising a base,

two receivers mounted on said base a transmitter also mounted on said base, three shafts individual to said receivers and transmitter respectively,

mon shaft, means comprising couplings for driving all said individual shafts from said common shaft, means for locking said individual shafts against rotation, key-operated means for unlocking the transmitter shaft and individual receiver 19 magnets for unlocking the receiver shafts.

GUSTAV EI-IRENBERG. 

